Sequelize integration test, with sample package support page

[guybedford]

This adds an integration test for sequelize, while also including a new documentation page linked to from the readme that we can use to document packages that need specific configurations for ncc.

In this case the dialectModule option for sequelize.

Resolves #397 and resolves #345.

[guybedford]

Note - this is passing with the asset relocator loader updates.

[styfle]

In your comment from vercel/webpack-asset-relocator-loader#39 it sounds like this fixes both sequelize and lighthouse.

Can you also add an integration test for lighthouse?

[guybedford]

Unfortunately there's another issue for Lighthouse - I've discussed this at #290 (comment).

Please update warl dependency so the tests pass

[codecov-io]

Codecov Report

Merging #407 into master will decrease coverage by 1.38%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #407      +/-   ##
==========================================
- Coverage   74.68%   73.29%   -1.39%     
==========================================
  Files          13       14       +1     
  Lines         395      397       +2     
==========================================
- Hits          295      291       -4     
- Misses        100      106       +6

Impacted Files	Coverage Δ
src/index.js	83.12% <0%> (-0.42%)	⬇️
src/@@notfound.js	0% <0%> (ø)	⬆️
src/sourcemap-register.js	0% <0%> (ø)

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[styfle]

Looks good. But why did coverage drop so much?

[guybedford]

The coverage change seems like it might have been delayed from one of the previous PRs? Because the diff is the same otherwise.

[styfle]

@guybedford Ok I think this is good to merge.

I missed the last release but it looks like it was a beta. Why was that? And should the next release be beta too or stable?